Question: Simplify the following expression: $\sqrt{10}+\sqrt{90}+\sqrt{40}$
First, try to factor any perfect squares out of the radicals. $= \sqrt{10}+\sqrt{90}+\sqrt{40}$ $= \sqrt{10}+\sqrt{9 \cdot 10}+\sqrt{4 \cdot 10}$ Separate the radicals and simplify. $= \sqrt{10}+\sqrt{9} \cdot \sqrt{10}+\sqrt{4} \cdot \sqrt{10}$ $= \sqrt{10}+3\sqrt{10}+2\sqrt{10}$ Finally, simplify by combining the terms. $= ( 1 + 3 + 2 )\sqrt{10} = 6\sqrt{10}$